AmerisourceBergen ( ABC) was upgraded at Citi to buy from neutral. The deal with Walgreens will be transformational, increasing international reach and adding purchasing power, said Citigroup. Price target is $62.

AmerisourceBergen was downgraded at ISI from buy to neutral. Valuation call, based on a $54 price target, ISI Group said.

Cardinal Health ( CAH) downgraded at Citi to neutral from buy. The loss of the contract with Walgreens will limit earnings growth, said Citigroup. Price target is $43.

Williams Partners ( WPZ) initiated at UBS with a neutral rating. While the company is a dominant midstream provider, commodity sensitivity remains, said UBS. Price target is $50.

STOCK COMMENTS/EPS CHANGES

Apple ( AAPL) estimates, target cut at Canaccord Genuity. Shares are now seen reaching $600. Estimates were also reduced, as the iPhone could lose market share this year, according to Canaccord Genuity.. Buy rating.

Cobalt International ( CIE) price target increased at UBS to $36. The appraisal of the Shenandoah well was impressive and the North Platt oil pay was above pre-drill estimates, said UBS.